Rep. Zawistowski joins Metropolitan District Commission ribbon cutting ceremony for the South Hartford Conveyance and Storage Tunnel Pump Station!

Rep. Zawistowski congratulated workers, engineers, and employees of the Metropolitan District Commission on Thursday during the official ribbon cutting ceremony for the South Hartford Conveyance and Storage Tunnel Pump Station!

This massive project has taken more than a decade to construct and bring online and will prevent Combined Sewer Overflows (CSOs) from entering the Connecticut River.

According the the MDC, "The new pump station will play an essential role in the operation of the SHCST, a four-mile-long deep rock tunnel designed to capture and temporarily store excess combined wastewater and stormwater during heavy rain events before conveying those flows to the Hartford Water Pollution Control Facility for treatment.

The tunnel, which extends beneath Hartford and West Hartford and was constructed 200 feet below ground in bedrock and can store approximately 41.5 million gallons of combined sewer overflows (CSOs), will protect local waterways and improve water quality throughout the region."

"This incredible storage facility will allow the MDC to treat and control the release of stormwater and wastewater overflow situations that previously might have been discharged untreated into the river," Rep. Zawistowski said. "Preventing combined sewer overflows is wildly expensive and takes years of planning, preparation, permitting and construction. I'm excited by this facility and hope it serves as a model for upriver communities in Massachusetts that continue to struggle with regulating and controlling these overflows."

According to the U.S. EPA, when the amount of water runoff exceeds the capacity of combined municipal wastewater treatment systems, untreated stormwater and wastewater is discharged into nearby waterbodies creating a Combined Sewer Overflow (CSO). These CSOs are subject to the National Pollutant Discharge Elimination System (NPDES) permitting program.

In August 2025, in response to complaints from local fishermen and others, Connecticut Reps. Zawistowski and Devin Carney (R-Old Lyme), sent a formal letter to Environmental Protection Agency to request assistance to prevent up-river states from continuing to discharge sewage and other harmful substances into the Connecticut River.  Those critical concerns, including the interstate water quality impact, public health risks, environmental justice, and the economic impact to tourism, recreation, and property values along the river corridor prompted ongoing discussions.

From those, the Cross-Border CT River Communities Initiative, an ad hoc group initiated by Rep. Zawistowski and Holyoke Mayor Joshua Garcia last fall in response to concerns about downriver pollution caused by CSOs from cities in Massachusetts, was created.

Last month, the group proposed hosting a regional Combined Sewage Outflow (CSO) Summit to focus on this important issue.

Still in the early planning stages, the group envisions the Summit as chance to acknowledge the environmental legacy of New England’s industrial past, highlight progress made, and discuss future plans to further restore clean water in the waterway. While the current focus has been on Massachusetts, the group expects to expand to include participants from the Connecticut River headwaters to Long Island Sound.